SnowFROC Abstract Byrne

Automated application security tools have been available for quite a while, but their manual counterparts are still doing quite well. This presentation will cover the relative strengths and weaknesses of both automated solutions, such as Web Application Firewalls (WAFs), source code review tools, and automated application scanners, and manual approaches, namely application penetration tests and manual code reviews. The presentation will conclude that automated tools are well suited for lower-priority applications, but manual analysis is important for critical applications.

Automated tools certainly have some strengths (namely low incremental cost, detecting simple vulnerabilities, and performing highly repetitive tasks). In addition to preventing some attacks, WAFs also have advantages for some compliance frameworks. However, automated solutions are far from perfect. To begin with, there are entire classes of very important vulnerabilities that are theoretically impossible for automated software to detect (at least until HAL comes online). Examples include complex information leakage, race conditions, logic flaws, design flaws, subjective vulnerabilities such as CSRF, and multistage process attacks.

Beyond that, there are many vulnerabilities that are too complicated or obscure to practically detect with an automated tool. Automated tools are designed to cover common application designs and platforms. Applications using an unusual layout or components will not be thoroughly protected by automated tools. Realistically, only the most vanilla of web applications written on common, simple platforms will receive solid code coverage from an automated tool.

On the other hand, manual testing is far more versatile. An experienced penetration tester can identify complicated vulnerabilities in the same way that an attacker does. Specific, real-world examples of vulnerabilities only recognizable by humans will be provided. The diversity of vulnerabilities shown will clearly demonstrate that all applications have the potential for significant vulnerabilities not detectible by automated tools.

Manual source code reviews present even more benefits by identifying vulnerabilities that require access to source code. Examples include “hidden” or unused application components, SQL injection with no evidence in the response, exotic injection attacks (e.g. mainframe session attacks), vulnerabilities in back-end systems, and intentional backdoors. Many organizations assume that this type of vulnerability is not a large threat, but source code can be obtained by disgruntled developers, by internal attackers when the repository isn’t properly secured, by exploiting platform bugs or path directory traversal attacks, and by external attackers using a Trojan horse or similar technique.

The Speakers: Charles Henderson & David Byrne

Charles Henderson has been in the security industry for over 15 years and manages the Application Penetration Testing and Code Review Practice at Trustwave. He has specialized in application security testing and application security assessment throughout his career but has also worked in physical security testing and network security testing.

David Byrne has almost a decade of experience in information security, specializing in web application penetration testing. Currently, he is a Senior Security Consultant in Trustwave’s SpideLabs division. Before joining Trustwave, David was the Security Architect at Dish Network. In addition to penetration testing, David has extensive experience working with developers and implementers to design security controls into applications from the ground up. He also has worked with governance and compliance groups to create security policies and standards documents.

In 2006, David started the Denver chapter of OWASP. In 2008, he released Grendel (grendel-scan.com), an open source web application security scanner. David has spoken at many industry events, including Black Hat, DEFCON, Toorcon, and the Computer Security Institute’s annual conference.